Differences Between One Way Slab and Two Way Slab

Reinforced Cement Concrete

When discussing the differences between one way slabs and two way slabs it is important to note that we are talking about concrete slabs. Concrete slabs are used in all different forms of construction where a thick slab is poured to be able to construct the ground floor of a building. The thickness of the concrete will vary depending on the use of the slab. Thicker concrete will be used as the support of the flooring and walls on the ground floor. Thinner concrete will be used between steel frames to help make the floors and ceilings of each level of the building. There are differences between one way slabs and two way slabs.

One Way Slab

It has supports on the two opposite sides only. This makes the structural action of the structure only one directional. The main reinforcement or main support beam is only found in one way slabs. To determine if the slab is one way, look to see if it is supported by all four sides. Then determine is the ratio between the longer span and shorter span is more than two. If it is more than two, then the slab is one way. The support will be found along the longer span. They are designed to transfer their general loads to the opposite support walls. The actual structural support of a one way slab is found on the shortest spans.

Two Way Slab

A two way slab has the main load carried in both directions. The main supports are found going in both directions. To determine if the slab is two way, figure the ratio between the longer span and the shorter span. If it is less than two, then the slab is two way. The transfer of the load is on all of the walls, all four become support walls. The supports will run perpendicular to each other. The actual structural support of a two way slab is found on two directions or on all four spans.

Differences Between One Way Slab and Two Way Slab

One way slabs are supported by beams on two sides only, while two way slabs are supported by all four sides. For a slab to be one way the ratio between the longer span and the shorter span must be greater than two. In order for a slab to be two way the ratio between the longer span and the shorter span must be less than two. If the ratio is equal to two, the slab is one way. The support or main reinforcement for one way slabs only go in one direction. The supports for two way slabs will go in both directions. One way slabs will behave in the same manner as a support beam, while with two way slabs is evenly distributed and will reduce bending and shifting.